The present invention relates to an indicating device and, in particular, to an indicating device which indicates the amount of transverse shear force exerted as a club or bat is swung prior to hitting a ball or other object so that a user can adjust the speed of the swing to obtain optimal results.
The transverse force indicating device in accordance with the present invention, may be utilized for teaching the user how to swing any rod-like object through an arcuate path. However, for purposes of illustration, the transverse force indicating device is described in a configuration useful in teaching a golfer how to swing a golf club through a preferred arcuate swing path using a suitable swing teaching apparatus such as that disclosed in U.S. Pat. Nos. 4,268,035 and 4,211,418.
In the swinging of any rod-like object, such as a golf club or baseball bat, it is essential that the object be swung through a proper arcuate path in order that the maximum power and timing be achieved so that a ball or the like will be propelled with both power and accuracy. However, a loss of control and timing frequently occurs when a golfer tries to exert too much force to hit the ball. Indeed, maximum power is delivered to a ball not by the exertion of maximum force throughout the stroke, but rather by a smooth, continuously accelerating swing, where the force is applied continuously rather than in a discontinuous or jerky manner.
Numerous devices have been developed to guide the rod-like object through the proper arcuate path to enable the user to acquire the "feel" of a proper swing so that, with practice, a desired swing will be achieved without requiring the use of the swing teaching apparatus. Patents disclosing examples of such swing teaching apparatus include:
______________________________________ U.S. Pat. No. Inventor Date ______________________________________ 2,448,905 Milner 9/7/48 2,655,378 Sheffer 10/13/53 3,400,933 Heiser 9/10/68 4,047,605 Rosenvold 9/13/77 ______________________________________
In each of the above patents, the device is, in one way or another, attached to the golf club. The swing teaching apparatus in application Ser. No. 10,554 , now U.S. Pat. No. 4,211,418, is not attached to the golf club as in the above patents and hence allows the user to "feel" the proper swing direction and thus be able to guide the club through the predefined arcuate path. The guiding is achieved by making it easier to rotate the swing teaching device when the golf club is swung through the predefined arcuate path. Because the user learns the proper swing by feeling it, rather than being constrained to it, it is believed that the transition to not using the teaching device, but still maintaining a proper swing, will be more quickly and easily made.
An implicit requirement of any teaching apparatus intended to teach swing control and timing as distinguished from swing position is that the golf club's weight distribution and balance be substantially the same whether or not the teaching apparatus is incorporated. Without the same weight distribution and balance the "feel" of the swing will be affected by the teaching apparatus. Attempts to duplicate that "feel" using a club without the teaching apparatus will then result in an incorrect swing making the teaching apparatus useless or even harmful in teaching correct swing timing and control.
While the swing teaching apparatus in U.S. Pat. Nos. 4,211,418 and 4,268,035 are thus valuable in teaching the proper swing direction, it does not indicate the amount of transverse force which the user is exerting against it. Hence, the swing may be in a proper arc but may still be improper and suboptional because it is jerky and discontinuous.
The present invention incorporates a transverse force indicating means whereby the force with which the club presses against the guide rod is indicated and thus can be applied more smoothly and continuously by the user. The transverse force indicating means may comprise a bifurcated member which may be the guide rod of the swing teaching apparatus or the club or attachment to the club where the bifurcated member comprises two parts interconnected in a normal coaxial configuration by a hinging device or a weak connecting member. If the club or club attachment exerts a transverse force greater than a predefined magnitude against the swing teaching machine guide rod, one part of the bifurcated member will bend out of coaxial alignment about the hinging device or will break off from the other member at the weak connecting member. Alternatively, the transverse force indicating means may be a strain gauge arrangement positioned on the guide rod, club or club attachment with a readout device interconnected to the strain gauge arrangement. The readout device is then calibrated and positioned so that the user can obtain a continuous feedback of the magnitude of the force exerted by the user. The user can then modify his swing until the exerted force remains within a specified value or satisfies some other predefined criteria.
In the preferred embodiment of the invention, the transverse force indicating means is configured to be responsive to a transverse force applied from any direction transverse to the common longitudinal axis of the two parts of the bifurcated member.
Of course, it will be appreciated that the transverse force may be applied without the necessity that the club or other device being swung by a user come in contact with an object such as the aforementioned swing teaching apparatus. Thus, in accordance with one embodiment of the invention, the club shaft to be swung may be bifurcated into first and second parts with an appropriate interconnecting apparatus therebetween to maintain a normal coaxial alignment. As the club accelerates through a swing, transverse forces are applied along the length of the bifurcated club shaft. If the relative transverse force between the two parts of the shaft caused by this acceleration through a swing is greater than a predefined amount, the two parts of the shaft will bend relative to each other.
In accordance with another embodiment of the invention, one or more strain gauge sensors may be positioned at a location along the shaft and may preferably be of a configuration which will measure the transverse force regardless of the direction along which force is applied so long as it is a transverse force.